1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3  * Copyright (c) 2011 The Chromium OS Authors.
4  */
5 
6 #ifndef __fdtdec_h
7 #define __fdtdec_h
8 
9 /*
10  * This file contains convenience functions for decoding useful and
11  * enlightening information from FDTs. It is intended to be used by device
12  * drivers and board-specific code within U-Boot. It aims to reduce the
13  * amount of FDT munging required within U-Boot itself, so that driver code
14  * changes to support FDT are minimized.
15  */
16 
17 #include <linux/libfdt.h>
18 #include <pci.h>
19 
20 /*
21  * A typedef for a physical address. Note that fdt data is always big
22  * endian even on a litle endian machine.
23  */
24 typedef phys_addr_t fdt_addr_t;
25 typedef phys_size_t fdt_size_t;
26 
27 #define FDT_ADDR_T_NONE (-1U)
28 #define FDT_SIZE_T_NONE (-1U)
29 
30 #ifdef CONFIG_PHYS_64BIT
31 #define fdt_addr_to_cpu(reg) be64_to_cpu(reg)
32 #define fdt_size_to_cpu(reg) be64_to_cpu(reg)
33 #define cpu_to_fdt_addr(reg) cpu_to_be64(reg)
34 #define cpu_to_fdt_size(reg) cpu_to_be64(reg)
35 typedef fdt64_t fdt_val_t;
36 #else
37 #define fdt_addr_to_cpu(reg) be32_to_cpu(reg)
38 #define fdt_size_to_cpu(reg) be32_to_cpu(reg)
39 #define cpu_to_fdt_addr(reg) cpu_to_be32(reg)
40 #define cpu_to_fdt_size(reg) cpu_to_be32(reg)
41 typedef fdt32_t fdt_val_t;
42 #endif
43 
44 /* Information obtained about memory from the FDT */
45 struct fdt_memory {
46 	fdt_addr_t start;
47 	fdt_addr_t end;
48 };
49 
50 struct bd_info;
51 
52 #ifdef CONFIG_SPL_BUILD
53 #define SPL_BUILD	1
54 #else
55 #define SPL_BUILD	0
56 #endif
57 
58 #ifdef CONFIG_OF_PRIOR_STAGE
59 extern phys_addr_t prior_stage_fdt_address;
60 #endif
61 
62 /*
63  * Information about a resource. start is the first address of the resource
64  * and end is the last address (inclusive). The length of the resource will
65  * be equal to: end - start + 1.
66  */
67 struct fdt_resource {
68 	fdt_addr_t start;
69 	fdt_addr_t end;
70 };
71 
72 enum fdt_pci_space {
73 	FDT_PCI_SPACE_CONFIG = 0,
74 	FDT_PCI_SPACE_IO = 0x01000000,
75 	FDT_PCI_SPACE_MEM32 = 0x02000000,
76 	FDT_PCI_SPACE_MEM64 = 0x03000000,
77 	FDT_PCI_SPACE_MEM32_PREF = 0x42000000,
78 	FDT_PCI_SPACE_MEM64_PREF = 0x43000000,
79 };
80 
81 #define FDT_PCI_ADDR_CELLS	3
82 #define FDT_PCI_SIZE_CELLS	2
83 #define FDT_PCI_REG_SIZE	\
84 	((FDT_PCI_ADDR_CELLS + FDT_PCI_SIZE_CELLS) * sizeof(u32))
85 
86 /*
87  * The Open Firmware spec defines PCI physical address as follows:
88  *
89  *          bits# 31 .... 24 23 .... 16 15 .... 08 07 .... 00
90  *
91  * phys.hi  cell:  npt000ss   bbbbbbbb   dddddfff   rrrrrrrr
92  * phys.mid cell:  hhhhhhhh   hhhhhhhh   hhhhhhhh   hhhhhhhh
93  * phys.lo  cell:  llllllll   llllllll   llllllll   llllllll
94  *
95  * where:
96  *
97  * n:        is 0 if the address is relocatable, 1 otherwise
98  * p:        is 1 if addressable region is prefetchable, 0 otherwise
99  * t:        is 1 if the address is aliased (for non-relocatable I/O) below 1MB
100  *           (for Memory), or below 64KB (for relocatable I/O)
101  * ss:       is the space code, denoting the address space
102  * bbbbbbbb: is the 8-bit Bus Number
103  * ddddd:    is the 5-bit Device Number
104  * fff:      is the 3-bit Function Number
105  * rrrrrrrr: is the 8-bit Register Number
106  * hhhhhhhh: is a 32-bit unsigned number
107  * llllllll: is a 32-bit unsigned number
108  */
109 struct fdt_pci_addr {
110 	u32	phys_hi;
111 	u32	phys_mid;
112 	u32	phys_lo;
113 };
114 
115 extern u8 __dtb_dt_begin[];	/* embedded device tree blob */
116 extern u8 __dtb_dt_spl_begin[];	/* embedded device tree blob for SPL/TPL */
117 
118 /**
119  * Compute the size of a resource.
120  *
121  * @param res	the resource to operate on
122  * @return the size of the resource
123  */
fdt_resource_size(const struct fdt_resource * res)124 static inline fdt_size_t fdt_resource_size(const struct fdt_resource *res)
125 {
126 	return res->end - res->start + 1;
127 }
128 
129 /**
130  * Compat types that we know about and for which we might have drivers.
131  * Each is named COMPAT_<dir>_<filename> where <dir> is the directory
132  * within drivers.
133  */
134 enum fdt_compat_id {
135 	COMPAT_UNKNOWN,
136 	COMPAT_NVIDIA_TEGRA20_EMC,	/* Tegra20 memory controller */
137 	COMPAT_NVIDIA_TEGRA20_EMC_TABLE, /* Tegra20 memory timing table */
138 	COMPAT_NVIDIA_TEGRA20_NAND,	/* Tegra2 NAND controller */
139 	COMPAT_NVIDIA_TEGRA124_XUSB_PADCTL,
140 					/* Tegra124 XUSB pad controller */
141 	COMPAT_NVIDIA_TEGRA210_XUSB_PADCTL,
142 					/* Tegra210 XUSB pad controller */
143 	COMPAT_SMSC_LAN9215,		/* SMSC 10/100 Ethernet LAN9215 */
144 	COMPAT_SAMSUNG_EXYNOS5_SROMC,	/* Exynos5 SROMC */
145 	COMPAT_SAMSUNG_EXYNOS_USB_PHY,	/* Exynos phy controller for usb2.0 */
146 	COMPAT_SAMSUNG_EXYNOS5_USB3_PHY,/* Exynos phy controller for usb3.0 */
147 	COMPAT_SAMSUNG_EXYNOS_TMU,	/* Exynos TMU */
148 	COMPAT_SAMSUNG_EXYNOS_MIPI_DSI,	/* Exynos mipi dsi */
149 	COMPAT_SAMSUNG_EXYNOS_DWMMC,	/* Exynos DWMMC controller */
150 	COMPAT_GENERIC_SPI_FLASH,	/* Generic SPI Flash chip */
151 	COMPAT_SAMSUNG_EXYNOS_SYSMMU,	/* Exynos sysmmu */
152 	COMPAT_INTEL_MICROCODE,		/* Intel microcode update */
153 	COMPAT_INTEL_QRK_MRC,		/* Intel Quark MRC */
154 	COMPAT_ALTERA_SOCFPGA_DWMAC,	/* SoCFPGA Ethernet controller */
155 	COMPAT_ALTERA_SOCFPGA_DWMMC,	/* SoCFPGA DWMMC controller */
156 	COMPAT_ALTERA_SOCFPGA_DWC2USB,	/* SoCFPGA DWC2 USB controller */
157 	COMPAT_INTEL_BAYTRAIL_FSP,	/* Intel Bay Trail FSP */
158 	COMPAT_INTEL_BAYTRAIL_FSP_MDP,	/* Intel FSP memory-down params */
159 	COMPAT_INTEL_IVYBRIDGE_FSP,	/* Intel Ivy Bridge FSP */
160 	COMPAT_SUNXI_NAND,		/* SUNXI NAND controller */
161 	COMPAT_ALTERA_SOCFPGA_CLK,	/* SoCFPGA Clock initialization */
162 	COMPAT_ALTERA_SOCFPGA_PINCTRL_SINGLE,	/* SoCFPGA pinctrl-single */
163 	COMPAT_ALTERA_SOCFPGA_H2F_BRG,          /* SoCFPGA hps2fpga bridge */
164 	COMPAT_ALTERA_SOCFPGA_LWH2F_BRG,        /* SoCFPGA lwhps2fpga bridge */
165 	COMPAT_ALTERA_SOCFPGA_F2H_BRG,          /* SoCFPGA fpga2hps bridge */
166 	COMPAT_ALTERA_SOCFPGA_F2SDR0,           /* SoCFPGA fpga2SDRAM0 bridge */
167 	COMPAT_ALTERA_SOCFPGA_F2SDR1,           /* SoCFPGA fpga2SDRAM1 bridge */
168 	COMPAT_ALTERA_SOCFPGA_F2SDR2,           /* SoCFPGA fpga2SDRAM2 bridge */
169 	COMPAT_ALTERA_SOCFPGA_FPGA0,		/* SOCFPGA FPGA manager */
170 	COMPAT_ALTERA_SOCFPGA_NOC,		/* SOCFPGA Arria 10 NOC */
171 	COMPAT_ALTERA_SOCFPGA_CLK_INIT,		/* SOCFPGA Arria 10 clk init */
172 
173 	COMPAT_COUNT,
174 };
175 
176 #define MAX_PHANDLE_ARGS 16
177 struct fdtdec_phandle_args {
178 	int node;
179 	int args_count;
180 	uint32_t args[MAX_PHANDLE_ARGS];
181 };
182 
183 /**
184  * fdtdec_parse_phandle_with_args() - Find a node pointed by phandle in a list
185  *
186  * This function is useful to parse lists of phandles and their arguments.
187  *
188  * Example:
189  *
190  * phandle1: node1 {
191  *	#list-cells = <2>;
192  * }
193  *
194  * phandle2: node2 {
195  *	#list-cells = <1>;
196  * }
197  *
198  * node3 {
199  *	list = <&phandle1 1 2 &phandle2 3>;
200  * }
201  *
202  * To get a device_node of the `node2' node you may call this:
203  * fdtdec_parse_phandle_with_args(blob, node3, "list", "#list-cells", 0, 1,
204  *				  &args);
205  *
206  * (This function is a modified version of __of_parse_phandle_with_args() from
207  * Linux 3.18)
208  *
209  * @blob:	Pointer to device tree
210  * @src_node:	Offset of device tree node containing a list
211  * @list_name:	property name that contains a list
212  * @cells_name:	property name that specifies the phandles' arguments count,
213  *		or NULL to use @cells_count
214  * @cells_count: Cell count to use if @cells_name is NULL
215  * @index:	index of a phandle to parse out
216  * @out_args:	optional pointer to output arguments structure (will be filled)
217  * @return 0 on success (with @out_args filled out if not NULL), -ENOENT if
218  *	@list_name does not exist, a phandle was not found, @cells_name
219  *	could not be found, the arguments were truncated or there were too
220  *	many arguments.
221  *
222  */
223 int fdtdec_parse_phandle_with_args(const void *blob, int src_node,
224 				   const char *list_name,
225 				   const char *cells_name,
226 				   int cell_count, int index,
227 				   struct fdtdec_phandle_args *out_args);
228 
229 /**
230  * Find the next numbered alias for a peripheral. This is used to enumerate
231  * all the peripherals of a certain type.
232  *
233  * Do the first call with *upto = 0. Assuming /aliases/<name>0 exists then
234  * this function will return a pointer to the node the alias points to, and
235  * then update *upto to 1. Next time you call this function, the next node
236  * will be returned.
237  *
238  * All nodes returned will match the compatible ID, as it is assumed that
239  * all peripherals use the same driver.
240  *
241  * @param blob		FDT blob to use
242  * @param name		Root name of alias to search for
243  * @param id		Compatible ID to look for
244  * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
245  */
246 int fdtdec_next_alias(const void *blob, const char *name,
247 		enum fdt_compat_id id, int *upto);
248 
249 /**
250  * Find the compatible ID for a given node.
251  *
252  * Generally each node has at least one compatible string attached to it.
253  * This function looks through our list of known compatible strings and
254  * returns the corresponding ID which matches the compatible string.
255  *
256  * @param blob		FDT blob to use
257  * @param node		Node containing compatible string to find
258  * @return compatible ID, or COMPAT_UNKNOWN if we cannot find a match
259  */
260 enum fdt_compat_id fdtdec_lookup(const void *blob, int node);
261 
262 /**
263  * Find the next compatible node for a peripheral.
264  *
265  * Do the first call with node = 0. This function will return a pointer to
266  * the next compatible node. Next time you call this function, pass the
267  * value returned, and the next node will be provided.
268  *
269  * @param blob		FDT blob to use
270  * @param node		Start node for search
271  * @param id		Compatible ID to look for (enum fdt_compat_id)
272  * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
273  */
274 int fdtdec_next_compatible(const void *blob, int node,
275 		enum fdt_compat_id id);
276 
277 /**
278  * Find the next compatible subnode for a peripheral.
279  *
280  * Do the first call with node set to the parent and depth = 0. This
281  * function will return the offset of the next compatible node. Next time
282  * you call this function, pass the node value returned last time, with
283  * depth unchanged, and the next node will be provided.
284  *
285  * @param blob		FDT blob to use
286  * @param node		Start node for search
287  * @param id		Compatible ID to look for (enum fdt_compat_id)
288  * @param depthp	Current depth (set to 0 before first call)
289  * @return offset of next compatible node, or -FDT_ERR_NOTFOUND if no more
290  */
291 int fdtdec_next_compatible_subnode(const void *blob, int node,
292 		enum fdt_compat_id id, int *depthp);
293 
294 /*
295  * Look up an address property in a node and return the parsed address, and
296  * optionally the parsed size.
297  *
298  * This variant assumes a known and fixed number of cells are used to
299  * represent the address and size.
300  *
301  * You probably don't want to use this function directly except to parse
302  * non-standard properties, and never to parse the "reg" property. Instead,
303  * use one of the "auto" variants below, which automatically honor the
304  * #address-cells and #size-cells properties in the parent node.
305  *
306  * @param blob	FDT blob
307  * @param node	node to examine
308  * @param prop_name	name of property to find
309  * @param index	which address to retrieve from a list of addresses. Often 0.
310  * @param na	the number of cells used to represent an address
311  * @param ns	the number of cells used to represent a size
312  * @param sizep	a pointer to store the size into. Use NULL if not required
313  * @param translate	Indicates whether to translate the returned value
314  *			using the parent node's ranges property.
315  * @return address, if found, or FDT_ADDR_T_NONE if not
316  */
317 fdt_addr_t fdtdec_get_addr_size_fixed(const void *blob, int node,
318 		const char *prop_name, int index, int na, int ns,
319 		fdt_size_t *sizep, bool translate);
320 
321 /*
322  * Look up an address property in a node and return the parsed address, and
323  * optionally the parsed size.
324  *
325  * This variant automatically determines the number of cells used to represent
326  * the address and size by parsing the provided parent node's #address-cells
327  * and #size-cells properties.
328  *
329  * @param blob	FDT blob
330  * @param parent	parent node of @node
331  * @param node	node to examine
332  * @param prop_name	name of property to find
333  * @param index	which address to retrieve from a list of addresses. Often 0.
334  * @param sizep	a pointer to store the size into. Use NULL if not required
335  * @param translate	Indicates whether to translate the returned value
336  *			using the parent node's ranges property.
337  * @return address, if found, or FDT_ADDR_T_NONE if not
338  */
339 fdt_addr_t fdtdec_get_addr_size_auto_parent(const void *blob, int parent,
340 		int node, const char *prop_name, int index, fdt_size_t *sizep,
341 		bool translate);
342 
343 /*
344  * Look up an address property in a node and return the parsed address, and
345  * optionally the parsed size.
346  *
347  * This variant automatically determines the number of cells used to represent
348  * the address and size by parsing the parent node's #address-cells
349  * and #size-cells properties. The parent node is automatically found.
350  *
351  * The automatic parent lookup implemented by this function is slow.
352  * Consequently, fdtdec_get_addr_size_auto_parent() should be used where
353  * possible.
354  *
355  * @param blob	FDT blob
356  * @param parent	parent node of @node
357  * @param node	node to examine
358  * @param prop_name	name of property to find
359  * @param index	which address to retrieve from a list of addresses. Often 0.
360  * @param sizep	a pointer to store the size into. Use NULL if not required
361  * @param translate	Indicates whether to translate the returned value
362  *			using the parent node's ranges property.
363  * @return address, if found, or FDT_ADDR_T_NONE if not
364  */
365 fdt_addr_t fdtdec_get_addr_size_auto_noparent(const void *blob, int node,
366 		const char *prop_name, int index, fdt_size_t *sizep,
367 		bool translate);
368 
369 /*
370  * Look up an address property in a node and return the parsed address.
371  *
372  * This variant hard-codes the number of cells used to represent the address
373  * and size based on sizeof(fdt_addr_t) and sizeof(fdt_size_t). It also
374  * always returns the first address value in the property (index 0).
375  *
376  * Use of this function is not recommended due to the hard-coding of cell
377  * counts. There is no programmatic validation that these hard-coded values
378  * actually match the device tree content in any way at all. This assumption
379  * can be satisfied by manually ensuring CONFIG_PHYS_64BIT is appropriately
380  * set in the U-Boot build and exercising strict control over DT content to
381  * ensure use of matching #address-cells/#size-cells properties. However, this
382  * approach is error-prone; those familiar with DT will not expect the
383  * assumption to exist, and could easily invalidate it. If the assumption is
384  * invalidated, this function will not report the issue, and debugging will
385  * be required. Instead, use fdtdec_get_addr_size_auto_parent().
386  *
387  * @param blob	FDT blob
388  * @param node	node to examine
389  * @param prop_name	name of property to find
390  * @return address, if found, or FDT_ADDR_T_NONE if not
391  */
392 fdt_addr_t fdtdec_get_addr(const void *blob, int node,
393 		const char *prop_name);
394 
395 /*
396  * Look up an address property in a node and return the parsed address, and
397  * optionally the parsed size.
398  *
399  * This variant hard-codes the number of cells used to represent the address
400  * and size based on sizeof(fdt_addr_t) and sizeof(fdt_size_t). It also
401  * always returns the first address value in the property (index 0).
402  *
403  * Use of this function is not recommended due to the hard-coding of cell
404  * counts. There is no programmatic validation that these hard-coded values
405  * actually match the device tree content in any way at all. This assumption
406  * can be satisfied by manually ensuring CONFIG_PHYS_64BIT is appropriately
407  * set in the U-Boot build and exercising strict control over DT content to
408  * ensure use of matching #address-cells/#size-cells properties. However, this
409  * approach is error-prone; those familiar with DT will not expect the
410  * assumption to exist, and could easily invalidate it. If the assumption is
411  * invalidated, this function will not report the issue, and debugging will
412  * be required. Instead, use fdtdec_get_addr_size_auto_parent().
413  *
414  * @param blob	FDT blob
415  * @param node	node to examine
416  * @param prop_name	name of property to find
417  * @param sizep	a pointer to store the size into. Use NULL if not required
418  * @return address, if found, or FDT_ADDR_T_NONE if not
419  */
420 fdt_addr_t fdtdec_get_addr_size(const void *blob, int node,
421 		const char *prop_name, fdt_size_t *sizep);
422 
423 /**
424  * Look at the compatible property of a device node that represents a PCI
425  * device and extract pci vendor id and device id from it.
426  *
427  * @param blob		FDT blob
428  * @param node		node to examine
429  * @param vendor	vendor id of the pci device
430  * @param device	device id of the pci device
431  * @return 0 if ok, negative on error
432  */
433 int fdtdec_get_pci_vendev(const void *blob, int node,
434 		u16 *vendor, u16 *device);
435 
436 /**
437  * Look at the pci address of a device node that represents a PCI device
438  * and return base address of the pci device's registers.
439  *
440  * @param dev		device to examine
441  * @param addr		pci address in the form of fdt_pci_addr
442  * @param bar		returns base address of the pci device's registers
443  * @return 0 if ok, negative on error
444  */
445 int fdtdec_get_pci_bar32(const struct udevice *dev, struct fdt_pci_addr *addr,
446 			 u32 *bar);
447 
448 /**
449  * Look at the bus range property of a device node and return the pci bus
450  * range for this node.
451  * The property must hold one fdt_pci_addr with a length.
452  * @param blob		FDT blob
453  * @param node		node to examine
454  * @param res		the resource structure to return the bus range
455  * @return 0 if ok, negative on error
456  */
457 
458 int fdtdec_get_pci_bus_range(const void *blob, int node,
459 			     struct fdt_resource *res);
460 
461 /**
462  * Look up a 32-bit integer property in a node and return it. The property
463  * must have at least 4 bytes of data. The value of the first cell is
464  * returned.
465  *
466  * @param blob	FDT blob
467  * @param node	node to examine
468  * @param prop_name	name of property to find
469  * @param default_val	default value to return if the property is not found
470  * @return integer value, if found, or default_val if not
471  */
472 s32 fdtdec_get_int(const void *blob, int node, const char *prop_name,
473 		s32 default_val);
474 
475 /**
476  * Unsigned version of fdtdec_get_int. The property must have at least
477  * 4 bytes of data. The value of the first cell is returned.
478  *
479  * @param blob	FDT blob
480  * @param node	node to examine
481  * @param prop_name	name of property to find
482  * @param default_val	default value to return if the property is not found
483  * @return unsigned integer value, if found, or default_val if not
484  */
485 unsigned int fdtdec_get_uint(const void *blob, int node, const char *prop_name,
486 			unsigned int default_val);
487 
488 /**
489  * Get a variable-sized number from a property
490  *
491  * This reads a number from one or more cells.
492  *
493  * @param ptr	Pointer to property
494  * @param cells	Number of cells containing the number
495  * @return the value in the cells
496  */
497 u64 fdtdec_get_number(const fdt32_t *ptr, unsigned int cells);
498 
499 /**
500  * Look up a 64-bit integer property in a node and return it. The property
501  * must have at least 8 bytes of data (2 cells). The first two cells are
502  * concatenated to form a 8 bytes value, where the first cell is top half and
503  * the second cell is bottom half.
504  *
505  * @param blob	FDT blob
506  * @param node	node to examine
507  * @param prop_name	name of property to find
508  * @param default_val	default value to return if the property is not found
509  * @return integer value, if found, or default_val if not
510  */
511 uint64_t fdtdec_get_uint64(const void *blob, int node, const char *prop_name,
512 		uint64_t default_val);
513 
514 /**
515  * Checks whether a node is enabled.
516  * This looks for a 'status' property. If this exists, then returns 1 if
517  * the status is 'ok' and 0 otherwise. If there is no status property,
518  * it returns 1 on the assumption that anything mentioned should be enabled
519  * by default.
520  *
521  * @param blob	FDT blob
522  * @param node	node to examine
523  * @return integer value 0 (not enabled) or 1 (enabled)
524  */
525 int fdtdec_get_is_enabled(const void *blob, int node);
526 
527 /**
528  * Make sure we have a valid fdt available to control U-Boot.
529  *
530  * If not, a message is printed to the console if the console is ready.
531  *
532  * @return 0 if all ok, -1 if not
533  */
534 int fdtdec_prepare_fdt(void);
535 
536 /**
537  * Checks that we have a valid fdt available to control U-Boot.
538 
539  * However, if not then for the moment nothing is done, since this function
540  * is called too early to panic().
541  *
542  * @returns 0
543  */
544 int fdtdec_check_fdt(void);
545 
546 /**
547  * Find the nodes for a peripheral and return a list of them in the correct
548  * order. This is used to enumerate all the peripherals of a certain type.
549  *
550  * To use this, optionally set up a /aliases node with alias properties for
551  * a peripheral. For example, for usb you could have:
552  *
553  * aliases {
554  *		usb0 = "/ehci@c5008000";
555  *		usb1 = "/ehci@c5000000";
556  * };
557  *
558  * Pass "usb" as the name to this function and will return a list of two
559  * nodes offsets: /ehci@c5008000 and ehci@c5000000.
560  *
561  * All nodes returned will match the compatible ID, as it is assumed that
562  * all peripherals use the same driver.
563  *
564  * If no alias node is found, then the node list will be returned in the
565  * order found in the fdt. If the aliases mention a node which doesn't
566  * exist, then this will be ignored. If nodes are found with no aliases,
567  * they will be added in any order.
568  *
569  * If there is a gap in the aliases, then this function return a 0 node at
570  * that position. The return value will also count these gaps.
571  *
572  * This function checks node properties and will not return nodes which are
573  * marked disabled (status = "disabled").
574  *
575  * @param blob		FDT blob to use
576  * @param name		Root name of alias to search for
577  * @param id		Compatible ID to look for
578  * @param node_list	Place to put list of found nodes
579  * @param maxcount	Maximum number of nodes to find
580  * @return number of nodes found on success, FDT_ERR_... on error
581  */
582 int fdtdec_find_aliases_for_id(const void *blob, const char *name,
583 			enum fdt_compat_id id, int *node_list, int maxcount);
584 
585 /*
586  * This function is similar to fdtdec_find_aliases_for_id() except that it
587  * adds to the node_list that is passed in. Any 0 elements are considered
588  * available for allocation - others are considered already used and are
589  * skipped.
590  *
591  * You can use this by calling fdtdec_find_aliases_for_id() with an
592  * uninitialised array, then setting the elements that are returned to -1,
593  * say, then calling this function, perhaps with a different compat id.
594  * Any elements you get back that are >0 are new nodes added by the call
595  * to this function.
596  *
597  * Note that if you have some nodes with aliases and some without, you are
598  * sailing close to the wind. The call to fdtdec_find_aliases_for_id() with
599  * one compat_id may fill in positions for which you have aliases defined
600  * for another compat_id. When you later call *this* function with the second
601  * compat_id, the alias positions may already be used. A debug warning may
602  * be generated in this case, but it is safest to define aliases for all
603  * nodes when you care about the ordering.
604  */
605 int fdtdec_add_aliases_for_id(const void *blob, const char *name,
606 			enum fdt_compat_id id, int *node_list, int maxcount);
607 
608 /**
609  * Get the alias sequence number of a node
610  *
611  * This works out whether a node is pointed to by an alias, and if so, the
612  * sequence number of that alias. Aliases are of the form <base><num> where
613  * <num> is the sequence number. For example spi2 would be sequence number
614  * 2.
615  *
616  * @param blob		Device tree blob (if NULL, then error is returned)
617  * @param base		Base name for alias (before the underscore)
618  * @param node		Node to look up
619  * @param seqp		This is set to the sequence number if one is found,
620  *			but otherwise the value is left alone
621  * @return 0 if a sequence was found, -ve if not
622  */
623 int fdtdec_get_alias_seq(const void *blob, const char *base, int node,
624 			 int *seqp);
625 
626 /**
627  * Get the highest alias number for susbystem.
628  *
629  * It parses all aliases and find out highest recorded alias for subsystem.
630  * Aliases are of the form <base><num> where <num> is the sequence number.
631  *
632  * @param blob		Device tree blob (if NULL, then error is returned)
633  * @param base		Base name for alias susbystem (before the number)
634  *
635  * @return 0 highest alias ID, -1 if not found
636  */
637 int fdtdec_get_alias_highest_id(const void *blob, const char *base);
638 
639 /**
640  * Get a property from the /chosen node
641  *
642  * @param blob		Device tree blob (if NULL, then NULL is returned)
643  * @param name		Property name to look up
644  * @return Value of property, or NULL if it does not exist
645  */
646 const char *fdtdec_get_chosen_prop(const void *blob, const char *name);
647 
648 /**
649  * Get the offset of the given /chosen node
650  *
651  * This looks up a property in /chosen containing the path to another node,
652  * then finds the offset of that node.
653  *
654  * @param blob		Device tree blob (if NULL, then error is returned)
655  * @param name		Property name, e.g. "stdout-path"
656  * @return Node offset referred to by that chosen node, or -ve FDT_ERR_...
657  */
658 int fdtdec_get_chosen_node(const void *blob, const char *name);
659 
660 /*
661  * Get the name for a compatible ID
662  *
663  * @param id		Compatible ID to look for
664  * @return compatible string for that id
665  */
666 const char *fdtdec_get_compatible(enum fdt_compat_id id);
667 
668 /* Look up a phandle and follow it to its node. Then return the offset
669  * of that node.
670  *
671  * @param blob		FDT blob
672  * @param node		node to examine
673  * @param prop_name	name of property to find
674  * @return node offset if found, -ve error code on error
675  */
676 int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name);
677 
678 /**
679  * Look up a property in a node and return its contents in an integer
680  * array of given length. The property must have at least enough data for
681  * the array (4*count bytes). It may have more, but this will be ignored.
682  *
683  * @param blob		FDT blob
684  * @param node		node to examine
685  * @param prop_name	name of property to find
686  * @param array		array to fill with data
687  * @param count		number of array elements
688  * @return 0 if ok, or -FDT_ERR_NOTFOUND if the property is not found,
689  *		or -FDT_ERR_BADLAYOUT if not enough data
690  */
691 int fdtdec_get_int_array(const void *blob, int node, const char *prop_name,
692 		u32 *array, int count);
693 
694 /**
695  * Look up a property in a node and return its contents in an integer
696  * array of given length. The property must exist but may have less data that
697  * expected (4*count bytes). It may have more, but this will be ignored.
698  *
699  * @param blob		FDT blob
700  * @param node		node to examine
701  * @param prop_name	name of property to find
702  * @param array		array to fill with data
703  * @param count		number of array elements
704  * @return number of array elements if ok, or -FDT_ERR_NOTFOUND if the
705  *		property is not found
706  */
707 int fdtdec_get_int_array_count(const void *blob, int node,
708 			       const char *prop_name, u32 *array, int count);
709 
710 /**
711  * Look up a property in a node and return a pointer to its contents as a
712  * unsigned int array of given length. The property must have at least enough
713  * data for the array ('count' cells). It may have more, but this will be
714  * ignored. The data is not copied.
715  *
716  * Note that you must access elements of the array with fdt32_to_cpu(),
717  * since the elements will be big endian even on a little endian machine.
718  *
719  * @param blob		FDT blob
720  * @param node		node to examine
721  * @param prop_name	name of property to find
722  * @param count		number of array elements
723  * @return pointer to array if found, or NULL if the property is not
724  *		found or there is not enough data
725  */
726 const u32 *fdtdec_locate_array(const void *blob, int node,
727 			       const char *prop_name, int count);
728 
729 /**
730  * Look up a boolean property in a node and return it.
731  *
732  * A boolean properly is true if present in the device tree and false if not
733  * present, regardless of its value.
734  *
735  * @param blob	FDT blob
736  * @param node	node to examine
737  * @param prop_name	name of property to find
738  * @return 1 if the properly is present; 0 if it isn't present
739  */
740 int fdtdec_get_bool(const void *blob, int node, const char *prop_name);
741 
742 /*
743  * Count child nodes of one parent node.
744  *
745  * @param blob	FDT blob
746  * @param node	parent node
747  * @return number of child node; 0 if there is not child node
748  */
749 int fdtdec_get_child_count(const void *blob, int node);
750 
751 /**
752  * Look in the FDT for a config item with the given name and return its value
753  * as a 32-bit integer. The property must have at least 4 bytes of data. The
754  * value of the first cell is returned.
755  *
756  * @param blob		FDT blob to use
757  * @param prop_name	Node property name
758  * @param default_val	default value to return if the property is not found
759  * @return integer value, if found, or default_val if not
760  */
761 int fdtdec_get_config_int(const void *blob, const char *prop_name,
762 		int default_val);
763 
764 /**
765  * Look in the FDT for a config item with the given name
766  * and return whether it exists.
767  *
768  * @param blob		FDT blob
769  * @param prop_name	property name to look up
770  * @return 1, if it exists, or 0 if not
771  */
772 int fdtdec_get_config_bool(const void *blob, const char *prop_name);
773 
774 /**
775  * Look in the FDT for a config item with the given name and return its value
776  * as a string.
777  *
778  * @param blob          FDT blob
779  * @param prop_name     property name to look up
780  * @returns property string, NULL on error.
781  */
782 char *fdtdec_get_config_string(const void *blob, const char *prop_name);
783 
784 /*
785  * Look up a property in a node and return its contents in a byte
786  * array of given length. The property must have at least enough data for
787  * the array (count bytes). It may have more, but this will be ignored.
788  *
789  * @param blob		FDT blob
790  * @param node		node to examine
791  * @param prop_name	name of property to find
792  * @param array		array to fill with data
793  * @param count		number of array elements
794  * @return 0 if ok, or -FDT_ERR_MISSING if the property is not found,
795  *		or -FDT_ERR_BADLAYOUT if not enough data
796  */
797 int fdtdec_get_byte_array(const void *blob, int node, const char *prop_name,
798 		u8 *array, int count);
799 
800 /**
801  * Look up a property in a node and return a pointer to its contents as a
802  * byte array of given length. The property must have at least enough data
803  * for the array (count bytes). It may have more, but this will be ignored.
804  * The data is not copied.
805  *
806  * @param blob		FDT blob
807  * @param node		node to examine
808  * @param prop_name	name of property to find
809  * @param count		number of array elements
810  * @return pointer to byte array if found, or NULL if the property is not
811  *		found or there is not enough data
812  */
813 const u8 *fdtdec_locate_byte_array(const void *blob, int node,
814 			     const char *prop_name, int count);
815 
816 /**
817  * Obtain an indexed resource from a device property.
818  *
819  * @param fdt		FDT blob
820  * @param node		node to examine
821  * @param property	name of the property to parse
822  * @param index		index of the resource to retrieve
823  * @param res		returns the resource
824  * @return 0 if ok, negative on error
825  */
826 int fdt_get_resource(const void *fdt, int node, const char *property,
827 		     unsigned int index, struct fdt_resource *res);
828 
829 /**
830  * Obtain a named resource from a device property.
831  *
832  * Look up the index of the name in a list of strings and return the resource
833  * at that index.
834  *
835  * @param fdt		FDT blob
836  * @param node		node to examine
837  * @param property	name of the property to parse
838  * @param prop_names	name of the property containing the list of names
839  * @param name		the name of the entry to look up
840  * @param res		returns the resource
841  */
842 int fdt_get_named_resource(const void *fdt, int node, const char *property,
843 			   const char *prop_names, const char *name,
844 			   struct fdt_resource *res);
845 
846 /* Display timings from linux include/video/display_timing.h */
847 enum display_flags {
848 	DISPLAY_FLAGS_HSYNC_LOW		= 1 << 0,
849 	DISPLAY_FLAGS_HSYNC_HIGH	= 1 << 1,
850 	DISPLAY_FLAGS_VSYNC_LOW		= 1 << 2,
851 	DISPLAY_FLAGS_VSYNC_HIGH	= 1 << 3,
852 
853 	/* data enable flag */
854 	DISPLAY_FLAGS_DE_LOW		= 1 << 4,
855 	DISPLAY_FLAGS_DE_HIGH		= 1 << 5,
856 	/* drive data on pos. edge */
857 	DISPLAY_FLAGS_PIXDATA_POSEDGE	= 1 << 6,
858 	/* drive data on neg. edge */
859 	DISPLAY_FLAGS_PIXDATA_NEGEDGE	= 1 << 7,
860 	DISPLAY_FLAGS_INTERLACED	= 1 << 8,
861 	DISPLAY_FLAGS_DOUBLESCAN	= 1 << 9,
862 	DISPLAY_FLAGS_DOUBLECLK		= 1 << 10,
863 };
864 
865 /*
866  * A single signal can be specified via a range of minimal and maximal values
867  * with a typical value, that lies somewhere inbetween.
868  */
869 struct timing_entry {
870 	u32 min;
871 	u32 typ;
872 	u32 max;
873 };
874 
875 /*
876  * Single "mode" entry. This describes one set of signal timings a display can
877  * have in one setting. This struct can later be converted to struct videomode
878  * (see include/video/videomode.h). As each timing_entry can be defined as a
879  * range, one struct display_timing may become multiple struct videomodes.
880  *
881  * Example: hsync active high, vsync active low
882  *
883  *				    Active Video
884  * Video  ______________________XXXXXXXXXXXXXXXXXXXXXX_____________________
885  *	  |<- sync ->|<- back ->|<----- active ----->|<- front ->|<- sync..
886  *	  |	     |	 porch  |		     |	 porch	 |
887  *
888  * HSync _|¯¯¯¯¯¯¯¯¯¯|___________________________________________|¯¯¯¯¯¯¯¯¯
889  *
890  * VSync ¯|__________|¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯|_________
891  */
892 struct display_timing {
893 	struct timing_entry pixelclock;
894 
895 	struct timing_entry hactive;		/* hor. active video */
896 	struct timing_entry hfront_porch;	/* hor. front porch */
897 	struct timing_entry hback_porch;	/* hor. back porch */
898 	struct timing_entry hsync_len;		/* hor. sync len */
899 
900 	struct timing_entry vactive;		/* ver. active video */
901 	struct timing_entry vfront_porch;	/* ver. front porch */
902 	struct timing_entry vback_porch;	/* ver. back porch */
903 	struct timing_entry vsync_len;		/* ver. sync len */
904 
905 	enum display_flags flags;		/* display flags */
906 	bool hdmi_monitor;			/* is hdmi monitor? */
907 };
908 
909 /**
910  * fdtdec_decode_display_timing() - decode display timings
911  *
912  * Decode display timings from the supplied 'display-timings' node.
913  * See doc/device-tree-bindings/video/display-timing.txt for binding
914  * information.
915  *
916  * @param blob		FDT blob
917  * @param node		'display-timing' node containing the timing subnodes
918  * @param index		Index number to read (0=first timing subnode)
919  * @param config	Place to put timings
920  * @return 0 if OK, -FDT_ERR_NOTFOUND if not found
921  */
922 int fdtdec_decode_display_timing(const void *blob, int node, int index,
923 				 struct display_timing *config);
924 
925 /**
926  * fdtdec_setup_mem_size_base() - decode and setup gd->ram_size and
927  * gd->ram_start
928  *
929  * Decode the /memory 'reg' property to determine the size and start of the
930  * first memory bank, populate the global data with the size and start of the
931  * first bank of memory.
932  *
933  * This function should be called from a boards dram_init(). This helper
934  * function allows for boards to query the device tree for DRAM size and start
935  * address instead of hard coding the value in the case where the memory size
936  * and start address cannot be detected automatically.
937  *
938  * @return 0 if OK, -EINVAL if the /memory node or reg property is missing or
939  * invalid
940  */
941 int fdtdec_setup_mem_size_base(void);
942 
943 /**
944  * fdtdec_setup_mem_size_base_lowest() - decode and setup gd->ram_size and
945  * gd->ram_start by lowest available memory base
946  *
947  * Decode the /memory 'reg' property to determine the lowest start of the memory
948  * bank bank and populate the global data with it.
949  *
950  * This function should be called from a boards dram_init(). This helper
951  * function allows for boards to query the device tree for DRAM size and start
952  * address instead of hard coding the value in the case where the memory size
953  * and start address cannot be detected automatically.
954  *
955  * @return 0 if OK, -EINVAL if the /memory node or reg property is missing or
956  * invalid
957  */
958 int fdtdec_setup_mem_size_base_lowest(void);
959 
960 /**
961  * fdtdec_setup_memory_banksize() - decode and populate gd->bd->bi_dram
962  *
963  * Decode the /memory 'reg' property to determine the address and size of the
964  * memory banks. Use this data to populate the global data board info with the
965  * phys address and size of memory banks.
966  *
967  * This function should be called from a boards dram_init_banksize(). This
968  * helper function allows for boards to query the device tree for memory bank
969  * information instead of hard coding the information in cases where it cannot
970  * be detected automatically.
971  *
972  * @return 0 if OK, -EINVAL if the /memory node or reg property is missing or
973  * invalid
974  */
975 int fdtdec_setup_memory_banksize(void);
976 
977 /**
978  * fdtdec_set_ethernet_mac_address() - set MAC address for default interface
979  *
980  * Looks up the default interface via the "ethernet" alias (in the /aliases
981  * node) and stores the given MAC in its "local-mac-address" property. This
982  * is useful on platforms that store the MAC address in a custom location.
983  * Board code can call this in the late init stage to make sure that the
984  * interface device tree node has the right MAC address configured for the
985  * Ethernet uclass to pick it up.
986  *
987  * Typically the FDT passed into this function will be U-Boot's control DTB.
988  * Given that a lot of code may be holding offsets to various nodes in that
989  * tree, this code will only set the "local-mac-address" property in-place,
990  * which means that it needs to exist and have space for the 6-byte address.
991  * This ensures that the operation is non-destructive and does not invalidate
992  * offsets that other drivers may be using.
993  *
994  * @param fdt FDT blob
995  * @param mac buffer containing the MAC address to set
996  * @param size size of MAC address
997  * @return 0 on success or a negative error code on failure
998  */
999 int fdtdec_set_ethernet_mac_address(void *fdt, const u8 *mac, size_t size);
1000 
1001 /**
1002  * fdtdec_set_phandle() - sets the phandle of a given node
1003  *
1004  * @param blob		FDT blob
1005  * @param node		offset in the FDT blob of the node whose phandle is to
1006  *			be set
1007  * @param phandle	phandle to set for the given node
1008  * @return 0 on success or a negative error code on failure
1009  */
fdtdec_set_phandle(void * blob,int node,uint32_t phandle)1010 static inline int fdtdec_set_phandle(void *blob, int node, uint32_t phandle)
1011 {
1012 	return fdt_setprop_u32(blob, node, "phandle", phandle);
1013 }
1014 
1015 /**
1016  * fdtdec_add_reserved_memory() - add or find a reserved-memory node
1017  *
1018  * If a reserved-memory node already exists for the given carveout, a phandle
1019  * for that node will be returned. Otherwise a new node will be created and a
1020  * phandle corresponding to it will be returned.
1021  *
1022  * See Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt
1023  * for details on how to use reserved memory regions.
1024  *
1025  * As an example, consider the following code snippet:
1026  *
1027  *     struct fdt_memory fb = {
1028  *         .start = 0x92cb3000,
1029  *         .end = 0x934b2fff,
1030  *     };
1031  *     uint32_t phandle;
1032  *
1033  *     fdtdec_add_reserved_memory(fdt, "framebuffer", &fb, &phandle, false);
1034  *
1035  * This results in the following subnode being added to the top-level
1036  * /reserved-memory node:
1037  *
1038  *     reserved-memory {
1039  *         #address-cells = <0x00000002>;
1040  *         #size-cells = <0x00000002>;
1041  *         ranges;
1042  *
1043  *         framebuffer@92cb3000 {
1044  *             reg = <0x00000000 0x92cb3000 0x00000000 0x00800000>;
1045  *             phandle = <0x0000004d>;
1046  *         };
1047  *     };
1048  *
1049  * If the top-level /reserved-memory node does not exist, it will be created.
1050  * The phandle returned from the function call can be used to reference this
1051  * reserved memory region from other nodes.
1052  *
1053  * See fdtdec_set_carveout() for a more elaborate example.
1054  *
1055  * @param blob		FDT blob
1056  * @param basename	base name of the node to create
1057  * @param carveout	information about the carveout region
1058  * @param phandlep	return location for the phandle of the carveout region
1059  *			can be NULL if no phandle should be added
1060  * @param no_map	add "no-map" property if true
1061  * @return 0 on success or a negative error code on failure
1062  */
1063 int fdtdec_add_reserved_memory(void *blob, const char *basename,
1064 			       const struct fdt_memory *carveout,
1065 			       uint32_t *phandlep, bool no_map);
1066 
1067 /**
1068  * fdtdec_get_carveout() - reads a carveout from an FDT
1069  *
1070  * Reads information about a carveout region from an FDT. The carveout is a
1071  * referenced by its phandle that is read from a given property in a given
1072  * node.
1073  *
1074  * @param blob		FDT blob
1075  * @param node		name of a node
1076  * @param name		name of the property in the given node that contains
1077  *			the phandle for the carveout
1078  * @param index		index of the phandle for which to read the carveout
1079  * @param carveout	return location for the carveout information
1080  * @return 0 on success or a negative error code on failure
1081  */
1082 int fdtdec_get_carveout(const void *blob, const char *node, const char *name,
1083 			unsigned int index, struct fdt_memory *carveout);
1084 
1085 /**
1086  * fdtdec_set_carveout() - sets a carveout region for a given node
1087  *
1088  * Sets a carveout region for a given node. If a reserved-memory node already
1089  * exists for the carveout, the phandle for that node will be reused. If no
1090  * such node exists, a new one will be created and a phandle to it stored in
1091  * a specified property of the given node.
1092  *
1093  * As an example, consider the following code snippet:
1094  *
1095  *     const char *node = "/host1x@50000000/dc@54240000";
1096  *     struct fdt_memory fb = {
1097  *         .start = 0x92cb3000,
1098  *         .end = 0x934b2fff,
1099  *     };
1100  *
1101  *     fdtdec_set_carveout(fdt, node, "memory-region", 0, "framebuffer", &fb);
1102  *
1103  * dc@54200000 is a display controller and was set up by the bootloader to
1104  * scan out the framebuffer specified by "fb". This would cause the following
1105  * reserved memory region to be added:
1106  *
1107  *     reserved-memory {
1108  *         #address-cells = <0x00000002>;
1109  *         #size-cells = <0x00000002>;
1110  *         ranges;
1111  *
1112  *         framebuffer@92cb3000 {
1113  *             reg = <0x00000000 0x92cb3000 0x00000000 0x00800000>;
1114  *             phandle = <0x0000004d>;
1115  *         };
1116  *     };
1117  *
1118  * A "memory-region" property will also be added to the node referenced by the
1119  * offset parameter.
1120  *
1121  *     host1x@50000000 {
1122  *         ...
1123  *
1124  *         dc@54240000 {
1125  *             ...
1126  *             memory-region = <0x0000004d>;
1127  *             ...
1128  *         };
1129  *
1130  *         ...
1131  *     };
1132  *
1133  * @param blob		FDT blob
1134  * @param node		name of the node to add the carveout to
1135  * @param prop_name	name of the property in which to store the phandle of
1136  *			the carveout
1137  * @param index		index of the phandle to store
1138  * @param name		base name of the reserved-memory node to create
1139  * @param carveout	information about the carveout to add
1140  * @return 0 on success or a negative error code on failure
1141  */
1142 int fdtdec_set_carveout(void *blob, const char *node, const char *prop_name,
1143 			unsigned int index, const char *name,
1144 			const struct fdt_memory *carveout);
1145 
1146 /**
1147  * Set up the device tree ready for use
1148  */
1149 int fdtdec_setup(void);
1150 
1151 /**
1152  * Perform board-specific early DT adjustments
1153  */
1154 int fdtdec_board_setup(const void *fdt_blob);
1155 
1156 #if CONFIG_IS_ENABLED(MULTI_DTB_FIT)
1157 /**
1158  * fdtdec_resetup()  - Set up the device tree again
1159  *
1160  * The main difference with fdtdec_setup() is that it returns if the fdt has
1161  * changed because a better match has been found.
1162  * This is typically used for boards that rely on a DM driver to detect the
1163  * board type. This function sould be called by the board code after the stuff
1164  * needed by board_fit_config_name_match() to operate porperly is available.
1165  * If this functions signals that a rescan is necessary, the board code must
1166  * unbind all the drivers using dm_uninit() and then rescan the DT with
1167  * dm_init_and_scan().
1168  *
1169  * @param rescan Returns a flag indicating that fdt has changed and rescanning
1170  *               the fdt is required
1171  *
1172  * @return 0 if OK, -ve on error
1173  */
1174 int fdtdec_resetup(int *rescan);
1175 #endif
1176 
1177 /**
1178  * Board-specific FDT initialization. Returns the address to a device tree blob.
1179  * Called when CONFIG_OF_BOARD is defined, or if CONFIG_OF_SEPARATE is defined
1180  * and the board implements it.
1181  */
1182 void *board_fdt_blob_setup(void);
1183 
1184 /*
1185  * Decode the size of memory
1186  *
1187  * RAM size is normally set in a /memory node and consists of a list of
1188  * (base, size) cells in the 'reg' property. This information is used to
1189  * determine the total available memory as well as the address and size
1190  * of each bank.
1191  *
1192  * Optionally the memory configuration can vary depending on a board id,
1193  * typically read from strapping resistors or an EEPROM on the board.
1194  *
1195  * Finally, memory size can be detected (within certain limits) by probing
1196  * the available memory. It is safe to do so within the limits provides by
1197  * the board's device tree information. This makes it possible to produce
1198  * boards with different memory sizes, where the device tree specifies the
1199  * maximum memory configuration, and the smaller memory configuration is
1200  * probed.
1201  *
1202  * This function decodes that information, returning the memory base address,
1203  * size and bank information. See the memory.txt binding for full
1204  * documentation.
1205  *
1206  * @param blob		Device tree blob
1207  * @param area		Name of node to check (NULL means "/memory")
1208  * @param board_id	Board ID to look up
1209  * @param basep		Returns base address of first memory bank (NULL to
1210  *			ignore)
1211  * @param sizep		Returns total memory size (NULL to ignore)
1212  * @param bd		Updated with the memory bank information (NULL to skip)
1213  * @return 0 if OK, -ve on error
1214  */
1215 int fdtdec_decode_ram_size(const void *blob, const char *area, int board_id,
1216 			   phys_addr_t *basep, phys_size_t *sizep,
1217 			   struct bd_info *bd);
1218 
1219 #endif
1220